In a sample of water specimens taken from a construction site, contained detectable levels of lead. Construct a confidence interval for the proportion of water specimens that contain detectable levels of lead.

square; 60; 225.

Step-by-step explanation:

1) using the vectors rules to calculate the lengths of the sides AB; BC; CD and AD. When AB=BC=CD=AD it means, the shape is a square of rhombus.

2) using the vectors rules to calculate the lengths of the diagonales AC and BD. When AC=BD it means, the shape is a square.

3) The perimeter of the square ABCD is 15*4=60.

4) The area of the square ABCD is 15*15=225.

All the details are in the attached picture; answers are marked with colour.